Help, high pitched whistle?

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Jun 26, 2002 | 12:07 PM

JMV

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Safety Car

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From: Western MA

Help, high pitched whistle?

This may be a dumb question for you guys, but my '69 350/350 gets a high-pitched whistling sound (loud) coming up from the carb (quadrajet) whenever rpm's reach 3200. It continues if I rev higher and stops as soon as rpms drop down. Doesn't matter whether driving or in parked in neutral. What is causing this? Car runs good at idle and when not pushing it. Also, when I hit gas hard, it seems to flood engine some and then clears and picks up speed. I do see some black smoke from exhaust when this occurs. please help, thanks! :confused:

[Modified by JMV, 4:08 PM 6/26/2002]

Jun 26, 2002 | 01:15 PM

MotorHead

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From: Who says "Nothing is impossible" ? I've been doing nothing for years.

Re: Help, high pitched whistle? (JMV)

Don't have the answer but I get it at idle, hope somone knows

Jun 26, 2002 | 02:53 PM

JMV

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From: Western MA

Re: Help, high pitched whistle? (MotorHead)

any guesses??

Jun 26, 2002 | 03:08 PM

Kingt

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From: Arlington Texas

Re: Help, high pitched whistle? (JMV)

You could use a stethoscope (or just a length of tubing) to try and locate the source. It may be so subtle at idle you can't hear it untill it reaches the higher RPM. It may be a vacuum leak around the base of the carb.?

Or, maybe someone dropped a whistle down the throat. :lol: :lol: :lol:

Jun 26, 2002 | 03:13 PM

kenincanada

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From: Victoria B.C. CANADA

Re: Help, high pitched whistle? (MotorHead)

You could try pulling your carb and tighten the screws holding the mounting plate to the body. Sucking air somewere.

Jun 26, 2002 | 03:19 PM

norvalwilhelm

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From: Waterloo ontario Canada

Re: Help, high pitched whistle? (JMV)

I have the same problem at all rpm. That high pitched whistle or is a whine?

Jun 26, 2002 | 03:25 PM

wcsinx

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Re: Help, high pitched whistle?

Well the physics of a whistle involves nothing more than an, in this case unwanted, oscillation of the air at high frequencies. It's possible that you're sucking air in from somewhere that shouldn't be as has already been suggested. Or there could also be something stuck, lodged, loose, out of place, etc. in the carb itself cause the air to move in an improper fashion.

Jun 26, 2002 | 03:34 PM

JMV

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From: Western MA

Re: Help, high pitched whistle? (JMV)

Thanks for all the answers, I think I will start with tightening in and around the carb. It is really loud, almost like a belt screech, but definitely a whistle out of carb area. It almost deafens the side-pipes! :crazy: